Flat bottom hulls are considered to have good planing characteristics due to the fact that there is a minimum amount of wetted surface and as a result there is a decrease in drag as the boat speed increases. However, flat bottom hulls lack stability, especially on turning, and also have a tendency to produce a rough ride in choppy water
On the other hand, V-bottom hulls, when used for planing, are generally formed with a relatively deep V at the bow which flattens out towards the stern. The V-shaped hull has the ability of being able to cut through heavy seas, although as the V cuts down into the water, the water is displaced along the V and has a tendency to slap against the bottom of the hull. Furthermore, the V bottom hull lacks lateral or rolling stability, particularly in the forward portion of the hull. Therefore the extent of the V in the hull is generally limited to the forward portion and does not extend generally aft of midship.
As an improvement U.S. Pat. No. 3,776,108 teaches a hull which has an overall V-shape with Vs of lesser depth formed on each side of the center line of the keel. This hull increases lateral stability but acts to increase the amount of wetted surface so that the planing characteristics of this hull are adversely affected.
As another improvement, U.S. Pat. No. 3,930,455 teaches a hull which has a pair of upwardly arched longitudinal channels on each side of the keel portion. Although this hull improves the planing characteristics, the hull is subject to capsizing during a relatively high speed type turn.